JDBC连接池(三)DBCP连接池

JDBC连接池(三)DBCP连接池

在前面的随笔中提到 了  1.JDBC自定义连接池  2.　C3P0连接池   

今天将介绍DBCP连接池

第一步要导入jar包   (注意：mysql和mysql 驱动的版本问题  ，驱动过低会造成下图异常)

 

创建db.properties 配置文件

DBCPUtils.java 文件

package com.study.jdbc.Utils;

import java.io.InputStream;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Properties;

import javax.sql.DataSource;

import org.apache.commons.dbcp.BasicDataSourceFactory;

public class DBCPUtils {

    private static DataSource dataSource;
    static{
        
        try {
            InputStream is=DBCPUtils.class.getClassLoader().getResourceAsStream("db.properties");
            Properties props=new Properties();
            props.load(is);
            //创建数据源
            System.out.println(props.getProperty("driver"));
            dataSource=BasicDataSourceFactory.createDataSource(props);
            System.out.println(dataSource);
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
        
    }
    public static DataSource getDataSource(){
        return dataSource;
    }
    public static Connection getConnection(){
        
        try {
            return dataSource.getConnection();
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
    }
}

TestDBCP.java

package cn.itheima.jdbc.test;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

import org.junit.Test;

import cn.itheima.jdbc.utils.DBCPUtils;

public class TestDBCP {

    @Test
    public void test1(){
        Connection conn=null;
        PreparedStatement pstm=null;
        ResultSet rs=null;
        try {
            conn=DBCPUtils.getConnection();
            String sql="select * from user";
            pstm=conn.prepareStatement(sql);
            rs=pstm.executeQuery();
            while(rs.next()){
                System.out.print(" userId ="+rs.getObject("userId")+"   ");
                System.out.println(" userName ="+rs.getObject("userName"));
                
            }
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
        
    }
    
    public static void main(String[] args) {
        Connection conn=null;
        PreparedStatement pstm=null;
        ResultSet rs=null;
        try {
            conn=DBCPUtils.getConnection();
            String sql="select * from user";
            pstm=conn.prepareStatement(sql);
            rs=pstm.executeQuery();
            while(rs.next()){
                System.out.print(" userId ="+rs.getObject("userId")+"   ");
                System.out.println(" userName ="+rs.getObject("userName"));

            }
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
        
    }
}